The present invention disclosed herein relates to a sensor network, and more particularly, to a data transmission method in a sensor network applied with a synchronous Receiver Initiated Transmission (RIT) low-power MAC protocol.
Sensor networks are used to provide services such as monitoring, tracing, reconnoitering, and automation using a plurality of communication nodes having abilities of sensing, processing, and communication. The sensor networks are means not for communication but for automated remote information collection. Particularly, Wireless Sensor Networks (WSNs) consist of sensor nodes having limited performances. The sensor nodes measure and collect information on surrounding environments in which respective sensor nodes are deployed. The collected information is delivered to a remote server or user through a wireless interface and a broadband network.
In the WSN, sensor nodes are low-priced devices operated by batteries. Accordingly, the life of a sensor node is limited to the life of a battery. This is because a battery can not be recharged or replaced even though the sensor node is paused when the battery dies.
Accordingly, WSNs require efficient power management to maximize the life of the network.
To meet these requirements, an asynchronous low-power MAC protocol of an RIT type has been proposed to assure reliability of sensor node and reduce power consumption. According to the asynchronous low-power MAC protocol of the RIT type, the reliability of a sensor node can be assured, and power consumption can be reduced. In order to reflect this trend, a RIT method has been proposed as a standard draft in IEEE 802.15.4e Low-Energy Subgroup that are standards related to sensor networks.
The asynchronous low power MAC protocol of the RIT type requires transmitting/receiving methods for protecting data conflict and expanding the life of a sensor node.